Palestinian relatives grieve over the body of Nayef Qarmut, a teenager killed on his way to school in an Israeli military drone strike, as he is prepared for...

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Despite the Obama administration’s claims that drones are a more effective tool than more traditional weapons, a new study found that civilians are ten times more likely to be killed by drones than by other means.

President Obama said in his May 23 national security speech that “by narrowly targeting our action against those who want to kill us and not the people they hide among, we are choosing the course of action least likely to result in the loss of innocent life.” Lawrence Lewis, a researcher at the Center for Naval Analyses, found this to be untrue.

Lewis’ study analyzed classified data about drone attacks in Afghanistan from mid-2010 and mid-2011, although it did not declassify the total number of civilians killed during that time period. That information remains unavailable to the public; estimates vary widely, but some groups have put the number of deaths in the thousands.

Another report, this one dealing with drone strikes in Yemen, was also published this week; it listed more than 80 people believed to be civilians killed or injured since 2009.

In Obama’s May speech, he said that “before any strike is taken, there must be near-certainty that no civilians will be killed or injured,” a ten-year-old boy was allegedly killed last month in a strike that targeted his older brother, who is said to have been a an al Qaeda militant.

Seventeen people were killed in a strike in Pakistan on Wednesday, and while Pakistani officials have claimed the victims were members of a militant group, their identities are still unknown.